For geotechnical engineers the energy sector is offering up particularly exciting new challenges. Mark Hansford talks to Atkins managing director of ground engineering David French.
Cast your mind back to the autumn of 2008 and it was a very gloomy place for British consulting engineers, and particularly those at work in the geotechnical sector. New Labour transport spending was drying up, the global recession was starting to bite and firms were suddenly feeling very exposed.
“Back in 2008 we saw the world as we knew it coming to an end,” says Atkins managing director of ground engineering David French. “After the unprecedented splurge of public spending from New Labour, we, like many others, were heavily UK focused. We knew we had to respond quickly as a lot of UK work was going to disappear.”
Atkins, like many others, identified that the energy market was one to target. “The energy industry is evolving at a pace never seen before in order to adapt to changing patterns of demand and a growing imperative to protect the planet.
Wave of opportunity
“This has presented us with a fantastic wave of opportunity, which spans nuclear new build, oil exploration in even deeper waters, offshore wind and many other areas such as underground gas storage and pipelines,” says French.
All are, as French says, “fascinating stories in themselves”, and not easy to crack.
“But there is a big difference between identifying an attractive sector and winning work in it,” notes French. “And it is a long way from designing earthworks on a road or railway to designing the foundations for an oil rig or offshore wind turbine.”
To access the various geotechnical opportunities in these areas, the firm had to recognise that the energy supply sector works to incredibly exacting standards and expects much of its technical consultants.
North Rankin A platform
The North Rankin A platform is one of the largest capacity gas production platforms in the world and serves as the central hub of the North West Shelf Project’s offshore gas production system.
Located 135km north-west of Karratha, western Australia, North Rankin A stands in 125m of water at a total height of 215m and combines drilling, production, utilities and accommodation facilities. The 54,000t production facility is supported on a conventional eight-leg steel jacket, secured to the seabed by 32 piles. The platform has a history of problems, because of difficult ground conditions, and piled foundations required major remedial works shortly after construction.
Atkins provided a team of geotechnical engineers from across the country to work on this technically complex project. A seismic assessment of the existing piled foundations in carbonate soils was carried out, including generation of artificial acceleration motions conforming to the uniform hazard design spectrum, a liquefaction assessment and representation of the pile group response as a series of dynamic impedance values.
And as well as being very technically demanding, work in this sector involves other demands, such as rapid deployment of staff internationally, and strict health and safety considerations - all in new geographies and harsh environments.
“That’s why we’ve dubbed it ‘geotechnics in the fast lane’,” French says. It’s a bold statement, but to be fair it is pretty scary stuff for a conventional engineer.
“This is not for the faint hearted,” says French. “These are technical challenges where you’ve got to throw away the codes and understand the problem. “When people start working in codes they tend to switch off their innovation brains.”
“The energy industry is evolving at a pave never seen before in order to adapt to changing patterns of demand”
David French, Atkins
“We are also operating in new geographies, where you are really up the jungle as it were. You’re in places like Kazakstan, Ajerbaijan and Oman. You just don’t have the BGS (British Geological Survey) memoir for those regions and there is not a lot to go on sometimes.”
Then there is the time factor. What clients need, says French, is a technical solution that is sometimes reliable, sometimes innovative, but always timely. Because the product is so valuable, programme is everything and so this is the sort of work where jumping on plane at short notice is common.
“All this caused us to think about where we were going to get the staff from,” he says. Internally, chiefly, was the answer.
“The particular demands of working in this sector have forced us to pull out all the stops, and use all our ingenuity, all our engineering skills, all our problem solving ability,” says French. “It has forced us to think about the who, the how, the what and the why. We have a big technical upskilling programme in progress to work through these and other concepts with our staff. It is hugely engaging for them.”
French is seeking inspiration from his old university geotechnics lecturer and leading geotechnical expert, Imperial College’s professor John Burland. Burland ingrained on French his view that geotechnics is as much a “dark art” as it is a science.
“We are dealing with a material that has been laid down by nature. It’s what makes it so fascinating and why it leads to rewarding careers,” he says. But it does need a certain type of person who can handle the vagaries of Mother Earth.
The BTC oil pipeline faces a variety of challenging geological environments, landscapes and geohazards along its 1,768km route through Azerbaijan, Georgia and Turkey.
They include landslides and debris flows, surface faults, liquefiable soils, underground cavities and even mud volcanoes in the Gobustan region of Azerbaijan. Atkins’ 10 year involvement with the BTC pipeline project has included geohazard input, routing studies for the entire route and planning.
It has also supervised ground investigations and supervised construction work in landslide-prone areas in Georgia. It has also provided investigation and geotechnical design input for facility site studies in Azerbaijan and Georgia. Currently, Atkins is undertaking a post-construction/operational audit of landslide hazards along the 1,076km Turkish section of the pipeline.
“The people are there,” says French. “Our instinctive reaction is to develop our own staff. What we need to teach them is the technical skills needed, but also the thinking skills,” he explains.
French says the core skill is finding the way to get to the nub of problems through an ability to “zoom in and zoom out” - understanding the bigger picture while being able to follow issues right down to the detailed specification.
There are also good knock-on effects of this technical upskilling in the firm’s traditional markets.
“The last three years have seen around a four fold increase in staff working in our energy geotechnics group”
David French, Atkins
The work - particularly in new regions such as the Middle East, North Africa, the Caucasus and the Far East - is also placing a renewed emphasis on understanding geology.
“An interesting aspect of this international growth is that it has brought the skills of our
engineering geologists to the fore,” says French. “They understand geological processes and can ‘read the ground’.”
Three years in and French says the plan is working. “These have been some of our most successful years ever,” he says. “Success is growth, and growth creates job opportunities.
“The last three years have seen around a four-fold increase in staff working in our energy geotechnics group, with around 30% of our 250 UK geotechnical staff now operating in this area.
“In the same period we have seen a similar increase in clients operating in the energy sector and it’s been particularly pleasing to establish long-term relationships with clients - such as BP, EDF and Fluor - where we bring our respective skills to develop leading edge technical solutions together.”
That trend is set to continue and French likes what he sees coming out of universities today.
Commercial and strategic reasons that justify the development of underground gas storage facilities in the UK are well understood and have been widely reported.
Atkins is currently working on six of the UK’s projects to create safe and functional gas storage in salt caverns. These include the King Street Energy development in Cheshire, for which it is assessing the geomechanical stability of the proposed salt caverns.
Atkins sent a team of rock mechanics and cavern design experts, which made detailed reviews of the geological dataset and identified an appropriate cavern layout, which was used to model the cavern stability and the working gas volume.
Atkins’ studies, incorporating finite element analyses, have indicated that it would be possible to develop caverns with a maximum diameter of 110m and a maximum height of 170m.